Chapter 9.4, Problem 29E

The national mean annual salary for a school administrator is $90,000 a year (The Cincinnati Enquirer; April 7, 2012). A school official took a sample of 25 school administrators in the state of Ohio to learn about salaries in that state to see if they differed from the national average.
a. Formulate hypotheses that can be used to determine whether the population mean annual administrator salary in Ohio differs from the national mean of $90,000.
b. The sample data for 25 Ohio administrators is contained in the DATAfile named Administrator. What is the p-value for your hypothesis test in part (a)?
c. At $\alpha =.05$ , can your null hypothesis be rejected? What is your conclusion?
d. Repeat the preceding hypothesis test using the critical value approach.